In the majority of cases, the steel cores of the cutting elements in this type of saws are coated with diamond powder or some other abrasive substance for sawing stone and concrete. In such applications, the machine equipment will normally be stationary and bulky, due to the fact that the limited flexibility of the typical wire saw requires the use of large guide sprocket wheels and strong wire loops. As a result of repeated bending and much use, the cutting element cores, threaded on the wire in broad proximity of or broad abutment with the wire or cable, tend to fracture particularly in the case of metal wires and or cables. This fracture tendency has been counteracted hitherto by increasing the diameter of the guide sprocket wheels and by greatly increasing the diameter of the wire or cable. On the other hand, if the distance between the inner surface of the cores and the wire is increased so as to afford the wire greater flexibility, there is a risk that the cores will be positioned obliquely by non-uniform pressure-forced penetration of elastomeric material into intermediate gaps from mutually opposite directions during manufacture, such cutting elements due to their misaligned periphery being prone to damage in a subsequent sawing operation. Non-uniform penetration of the elastomeric material is also liable to occur when the gap is narrow. Conventional designs are disclosed, for instance, in Patent Specifications U.S. Pat. No. 4,907,564, U.S. Pat. No. 3,884,212 and EP 0 364 322.
With the intention of creating more flexible wire saws suited as lighter machine equipment for sawing stone, for instance for hand-held chain-saw like machinery, endeavours must be directed towards reducing the diameter of the wire or cable while at the same time attaining a wire loop which can utilize the increased flexing ability with sufficient endurance against repeated bending around drive wheels and guide sprocket wheels, which would enable that the diameter of said wheels be reduced and the manageability of the equipment therewith improved. A reduction in the diameter of the guide sprocket wheel in portable tools of the chain-saw kind can further increase the manageability of the tool in use by virtue of the fact that this will enable more than one guide sprocket wheel to be mounted on the outer end of the saw blade. An example of a similar tendency in chain saws is disclosed in patent publication U.S. Pat. No. 4,654,972.